Sunday, October 18, 2009

Getting Overheated

The recent deaths in a Sedona "sweat lodge," now being discussed at a couple of my regularreads, caught my eye because I am a bit of a sauna fanatic. I don't think I'm a fanatic, of course, but in a discussion with an Estonian-American friend on the subject this week, I could see that look in her eyes. And when an Estonian thinks you're fanatic about sauna, well...

I've done a sweat lodge once, too. I didn't like it as much because of the smoke (don't like smoke-saunas either), and there wasn't a cool shower or stream or snowbank for afterwards. To me, that's an essential part of the experience.

I like sauna because it feels good. I attach no spiritual significance to it; the sweat lodge had a bit of speaking one's thoughts, which I found pleasant in the way one might find a church service pleasant. But it's the hot and cold that I really enjoy.

When I saw the thermometer register 100 C in my friend's sauna, I asked if the thermometer was correct. My friend is a scientist, and he said it was. That took me aback. That's the temperature at which water boils and eggs cook. If the protein in eggs cooks at sauna temperature, then what is happening to the delicate insides of my lungs?

With more consideration, however, I realized that the air (a poor heat-transfer medium with a relatively small specific heat) would be cooled by my nasal passages and throat, the opposite of what happens when you're outside in winter. So my lungs were safe.

While I'm in sauna, I'm monitoring my body's response. Warming, sometimes with shivering, then sweating. You're not really getting the benefit, my Estonian friends tell me, until you're sweating. I've found it can take a surprisingly long time for sweating to start. Then I reach the right temperature for cold-water quenching. That's usually done with a shower. I suspect that breathing has a lot to do with the production of the endorphins that must account for the pleasant sensations of sauna. Breathing can be strange in sauna. If I tense up, it becomes difficult. If I go with the sensations, it's all right. It's more difficult with steam, and I prefer a dry sauna for that reason. When the cold water hits me, I gasp involuntarily, lots of air comes in. I haven't had a chance to roll in the snow, but I know it would be delightful.

It takes some learning to do this. People who are not accustomed to such things panic, as I did just a bit at first. It sounds crazy, especially the rolling in the snow part, before you've experienced it. It's important to keep in mind that you can leave the sauna at any time and you don't have to quench yourself.

There are a number of differences from what was going on in Sedona, of course. As is discussed at the links above, it was one of those promises of enlightenment if you just do as you're told by the guru. So people were doing what they were told and might not have paid attention to their bodies' saying "enough." And in a sweat lodge, as is noted in the comment thread at Emptywheel, hot stones are brought in and water poured on them to generate steam. What I haven't seen said is that herbs are put on the stones to generate perfumed smoke as well. I particularly didn't like this kind of smoke, which I found irritating. I'm wondering what kinds of herbs were used in Sedona. Some desert herbs have ephedrine in them, which could provoke bad physiological responses.

I do think that some of the common wisdom in places unaccustomed to sauna or sweat lodges is misleading. Harvard Medical School provides some cautions, but says that sauna should be safe for reasonably healthy people. I haven't noticed my heart rate increasing particularly, as they claim, which may be a function of that tendency to panic at first. Here's a paper with more detail, but it is by Finns, and they're likely to agree with me that sauna is a good thing. Both agree that people with heart disease should probably forego this particular pleasure.